Controlling apparatus for refrigerating systems



Jan. 10, I939. J. KIRGAN ET AL 2,143,560

CONTROLLING APPARATUS FOR REFRIGERATING SYSTEMS Filed Oct. 24, 1936 2 Sheets-Sheet 1 IN V EN TORS JOZEX- AFA I EA N AND Y GEORGE coon/m.

TM? A TTORNEY Jan. 10, 1939. J. KIRGAN ET AL CONTRQLLINGAPRARATUS FOR REFRIGERATING SYSTEMS Filed Oct. 24, I936 2 Sheets-Sheet 2 Patented Jan. 10, 11939 UNITED STATES PATENT, OFFICE oon'rnonnnm APPARATUS non REFRIG- ERATING SYSTEMS John Kirgan, Easton, Pa., and John A. MacLean and George H. Woodard, Phillipsburg, N. J., assignors to Ingersoli-Rand Company, Jersey City, N. 1., a corporation of New Jersey Application October 24, 1936', Serial No. 197,356

r 17 Claims.

means dependent upon a device driven at a speed corresponding to that of said unit for actuating and circulating a pressureagent lthrough which the operation of said unit can begslispended whenever its speed rises above a 'iredeteririined value, said device having in combination therewith conevacuator for the evaporator and a power unit for operating the evacuator, with means for cutting ofi the power medium supplied to said unit whenever the pump for removing the cooled refrigerant from the evaporator stops or fails to properly discharge said refrigerant, or whenever the refrigerant in said evaporator threatens to' inflict damage upon other partsof the system.

with the ioregoing and other objects and advantages in view the nature of the invention will be made clear inthe following description which, taken with the drawings; discloses one or more embodiments of the invention. We of course reserve the right to make changes which do not depart from the principle of the invention or exceed the scope and spirit 0! the appended claims. a

In the drawings Figure 1 shows an outline partly in section of a refrigerating system with controlling apparatus according to our invention, and

Figure 2 is a more or less diagrammatic view, partly in sectionof a modified construction of the controlling apparatus.

On the drawings the same numerals identify the same parts throughout.

Referring first to Figure 1 we show 'at I a closed receptacle called an evaporator to which a liquid refrigerant in finely divided form is supplied through an inlet header 2 having a number nections by which the starting ofsaid unit andv to deliver the refrigerant from the evaporator, an

of jet openings through which the refrigerant issues in the form of a spray. Some of the liquid is vaporized in the evaporator I and this vapor iswithdrawn through an opening 3 which is connected to an evacuator 65 such as a centrifugal compressor of the conventional design, as is illustrated in Fig. 2. This compressor may be driven by a unit such as a steam turbine enclosed in a housing 4. The compressor connected to the vapor outlet 3 not only removes vapor but maintains a very high'vacuum in the evaporator I, thus insuring a continuous vaporization of part of the refrigerant. The bulk of the refrigerant remains liquid and is cooled in theevaporator I by 'the formation ofvapor therein, the cooled 'iiquid being'withdrawn through a discharge conduit 5 connected to the bottom of the evaporator.

The conduit 5 leads to the space 6 which may be an air cooler or any other .device wherein the refrigerant absorbs heat.. It is afterwards retumed'at a higher temperature to the header 2 and is cooled again for further use.

The turbine for driving the evacuator is supplied with a power medium, such as steam, through a pipe or conduit 1 in which there is a controlling valve 8. This valve is manually opened to initiate operation of the turbine and the system. However, as soon as the system is in operation this valve 8 is hydraulically controlled and is thus automatically opened or closed in accordance with the operating conditions of the system. For this purpose we provide'a reservoir 9 from which 011 or other pressure agent is withdrawn by a pump "la and forced through a pipe Ii to a casing I2 containing a piston It. Attached to this piston is a rod I! that projects to the outside of the casing l2 and is connected to the valve means 8. The device indicated at lfla runs at a speed corresponding to the speed of the evacuator since both the evacuator 65 and the pump Illa are connected to the turbine shaft 66 (see Fig. 2). As long as proper conditions exist the pressure of the oil or the other liquid with-. drawn from the reservoir 9 will be exerted on the piston Hi to keep the valve 8 open so that the operation of .the refrigerating system can be continued.

Within the casing I2 is a spring 15 which tends -to close the valve 8, and to cause this valve to remain open, the oil drawn from the reservoir 8 by the pump lllais forced into the top of the casing 12 through a pipe l6 at a pressure which overcomes the spring l5 and forces the piston I 3 outward. The apparatus for controlling the valve 8 so that it remains open but closes when recasing l2 of the piston l3, but a system of additional parts and members to facilitate opening the valve 8 at starting, to prevent the normal speed of the turbine from being exceeded and to bring about the closing of the valve if for any reason the flow of the cooled refrigerant to the coil 6 is stopped or the cooled refrigerant rises to a level that is too high in the evaporator I and threatens to enter the outlet 3 so as to damage the evacuator.

To this end the casing I! of the valve 8 has a projection which affords means for pivotally mounting thereon a lever l8. This lever is supported intermediate its ends, one of which is pinned to the rod l4 and the other end to one extremity of the lever l9 by a suitable connection 20. The opposite end of the lever I9 is pinned at 2| to another lever 22 mounted between its ends on a'flxedfulcrum 23. Adjacent the pin 2| the lever l9 has a pin-and-slot connection with a rod 24 of a piston valve 25 in the casing 26. This piston valve has a recess 21 extending around it adjacent the end which is nearer to the rod 24 and adjacent the other or inner end has a similar circumferential recess 28. The lever l9 has a handle 29 adjacent the connection 20 so that it can be, manipulated to start the system.

We also connect another pump device |0b to be driven by the turbine 4 and to withdraw liquid from the reservoir 9'and force it through a pipe 3|! into a casing 3| containing a piston 32. The piston 32 is joined by a rod 33 to the end of the lever 22 remote from the pin 2| and the effect is such that when the piston 32 is moved outward or downward with respect to the casing 3| the lever 22 is so actuated that it tends to move the connected end of the lever l9 upward. In the casing 3| a spring 34 opposes the movement of the piston 32 under the action of the pressure of the liquid admitted through the pipe 30.

With these connections the turbine in the housing 4 can be easily started and prevented from exceeding a given speed. When the turbine is not running the pumps Illa and lllb will be motionless and the spring |5 will act upon the means comprising the piston l3 and valve 8 so as to hold the valve 8 shut. Also the spring 34 will move the piston 32 to the top of its range and the lever member |9 will therefore be held by the lever members l8 and 22 in its lowest position. To start, the operator must pull the handle 29 of the lever I9 upward. The lever l9 then swings at little about the pin 2|, moving the valve 24 outward somewhat but not enough to cut off the pipe II from the pipe l6. The valve 8 is thus opened slightly so that steam flows into the housing of the turbine 4 and starts the latter, and the pumps Illa and lllb are also set into operation. Oil then flows through the connections H and I6 entering the casing 2 and forcing the piston I3 outward to open the valve further. Thus the turbine soon reaches the full operating speed. Any oil that is below the piston |3 as it moves downward is forced out through a pipe or connection 35which now communicates with a pipe or connection 36 through the recess 2'! in the valve 24 and is returned to the reservoir 9.

With the turbine now running the pump lob forces oil into the casing 3|, moves the piston downward and lifts the end of the lever 22 connected to the lever Hi. This movement may result in causing the valve 24 to close the ports in the casing 25 leading to the pipes I6 and 35. The oil in the top of the casing If, however, will quired, comprises not only the pump Ia and thecontinue to hold the valve 8 fully open, and the turbine continues to run at the fixed speed desired. If, however, the selected maximum speed of the turbine is exceeded the piston or element 32 will be moved outward, since the turbine is directly connected to the pump |8b an increase in speed of the turbine will increase the speed of the pump and the pressure of the fluid supplied thereby, far enough to lift the end of the lever l9 connected to the valve rod 24 and move this valve so as to put the pipe 35 in connection with the pipe Pressure fluid will now enter the casing l2 below the piston l3, lift this piston and shut the valve 8. The same movement of the valve 24 connects the pipe is around the inner end of this valve with the pipe 3'! which delivers to the pipe 36 and the oil above the piston I3 is thus returned to the reservoir 9.

The top of the casing 3| is joined by a pipe or connection 38 to the reservoir 9 and. this pipe contains a. hand adjustable valve 39. By this valve, the pressure with which the piston 32 will act to make the valve 8 close, can be regulated. Thus the maximum speed of the turbine and the evacuator can be determined.

The pipe II is also connected to the reservoir 9 by a return pipe 40. This pipe is normally kept closed by a valve 4|, but which may open and bring about closing of the valve 8 when the refrigerating system stops operating or when some danger arises in the system outside of the turbine 4 and which makes further operation inadvisable. The valve 4| for the release connection or pipe 40 is mounted in a casing comprising an extension 42 which surrounds the stem 43 of the valve 4|. This stem is encircled by a spring 44 engaging a head 45 on the valve stem and pushing against this head so as to tend to open the valve.4l. A diaphragm 46 engages the head 45 and over this diaphragm is a cover 41 connected by a pipe 48 to any suitable source of pressure which for the sake of convenience is here shown as the refrigerant pipe 5 leading to the space 6. In this pipe adjacent the evaporator is a force pump or the like means 49 operated by the motor 58 and the length of the pipe 5 leading to the space 6 has a non-return-check valve 50 therein. The connection 48 is united to the pipe 5 between pump 49 adjacent the evacuator and the one-way valve 50. Hence so long as the pump 49 is working and forces refrigerant to the space 6 the pressure of this refrigerant in the pipe 48 forces the diaphragm 46 against the head 45 and keeps the valve 4| closed. With these connections, if the pressure falls in the pipe 48, the valve 4| opens, and the pressure abovethe piston l2 is immediately reduced because the discharge of the pump Illa is now directed back into the reservoir 9 through the open pipe 40, and the pressure agent is thus rendered inefiective to hold the valve 8 open. Thus if for any reason refrigerant stops flowing under pressure in the pipe 5 the turbine is shut down and the production of further refrigeration effect is impossible until the defect has been remedied. This arrangement also Y renders it impossible for the turbine to operate automatically until after the pump 48 has been started and the refrigerant put in circulation.

Hence in practice the refrigerant will be cooled in the evaporator and transmitted to the space 6, and as long as the refrigerant is forced under pressure through the pipe 5 the valve 4| will be shut. If the maximumspeed of the turbine and evacuator is exceeded the pressure fluid in the casing 3| moves the valve 24 up- I pipe 48 has a regulating valve 60 therein simiward and the oil circulated by the pump Ilia enters the casing I! through pipe 35, under the piston l3 to lift this piston and close the valve 8, and the oil above the piston l3 isexhausted through the pipes l6 and 31 and flows back into the reservoir 9. If for any reason the pump 49 should stop, so that the liquid in the pipe 48 is no longer under pressure, the release valve 4| will open. Fluid circulated by the pump Ilia.

down. Unde these conditions the spring I5 will close the valve 8 and stop the turbine and the evacuator.

Whenever the pump stops the pressure of the liquid in the pipe 48 will drop to such an extent as to allow the valve 4| to open, and bring about a complete shut down of the system. The result would be as before to short circuit the pump Ma and allow the valve 8 to shut.

Figure 2 shows a modification in which the lar to the valve 39. A branch pipe 6| from the pipe 48 leadsinto the evaporator to a casing 62 containing a rotary valve 63. This casing alsohas a drain pipe connection 64 leading to the sewer. The rotary valve 63 is connected to the float lever 5|. In normal operation the pressure of the cooled refrigerant in the pipe 48 will hold the valve 4| in the casing 42 closed as' before. If the means for discharging the refrigerant, such as the pump 49, stops this valve will open and if the refrigerant becomes too deep in the evaporator thefloat lever 5| will be lifted to move the valve 63 so as to open cominun'ication between the pipe 6| and 64. The pressure in the pipe 48 will thus drop to permit the valve 4| to open with the sameefiect as before whereby the pump Illa will circulate oil from the reservoir 9 and back into the reservoir immediately through the pipe so that the piston l3 will be free to move upward and close the valve 8.

Fromthe foregoing description it will be clear that the controlling apparatus will operate effectively for the intended purpose. The connections are very easy to make and the parts are simple in operation and certain to function as required.

We claim: I

-I.I-n{ a refrigerating system comprising an evaporator and a variable speed unit to remove vapor from the evaporator, fluid pressure operated means tocontrol operation of said unit, means to supply fluid under pressure to said fluid pressure operated means operated by said variable speed unit and varying the pressure in accordance with variations in the speed of the unit, and independent pressure responsive means 'riormally rendering the last said means operative.

2.111 a refrigerating system comprising an evaporator and a variable speed unit to remove vapor from the evaporator, means to supply power medium to the unit, fluid pressure operated 3. In a refrigerating system comprising an evaporator having inlet and discharge means for liquid, and a variable speed unit to cause removal of vapor from the evaporator, means to transmit a power medium to the unit, a device for placing an operating fluid under pressure operated by said variable speed unit and changing the pressure in accordance with variations in the speed of the unit, means operated by changes in the pressure of the fluid to control the transmission of said medium, and means acting in response to a decrease in the pressure of the liquid discharged from the evaporator to relieve said pressure fluid to cause the last said means to suspend the transmission of power medium.

4. In a refrigerating system comprising an evaporator having inlet and discharge means for liquid, and a variable speed unit-to cause removal of vapor from the evaporator, means to transmit a power mediumto the unit, a device for placing an operating fluid under pressure operated by said variable speed unit and changing the pressure in accordance with variations in the speed of the unit, means operated by changes in the pressure of the fluid to control the transmission of said medium, and means controlled by liquid discharging from the evaporator and acting responsively to a falling pressure of such ri liquid to relieve the pressure fluid to cause the last said means to suspend the transmission of power medium.

5. In a refrigerating system comprising. an evaporator adapted to discharge refrigerant, and a variable speed unit to remove vapor from the evaporator, means to supply power medium to the unit, a device to place an operating fluid under pressure operated by said variable speed unit and changing the pressure in accordance with variations in the speed of the unit, fluid pressure means actuated by said fluid under pressure associated with the supply means to regulate the supply of power medium to the unit. means to renderthe fluid under pressure ineffective to actuate said fluid pressure means, and pressure operated means normally maintaining the last said means inoperative.

6. In a refrigerating system comprising an evaporator adapted to discharge refrigerant, and

a variable speed unit to remove vaipor from the tuated valve to maintain it open.

'7. In a refrigerating systemban evaporator, a supply conduit for a medium to furnish power for the removal of vapor from said evaporator, means for discharging refrigerant from the evaporator, means tomaintain the flow of medium through the conduit dependent upon the pressure of the-refrigerant discharged from the evap orator, and means responsive to a certain level of the refrigerant in the evaporator to,reduce the pressure of the discharged refrigerant and thereby cause suspension of the flow of said medium.

8. The combination of an evaporator having a pump to discharge refrigerant therefrom, a conduit to supply power medium to be expended in the removal of vapor from the evaporator, a device to place a fluid under pressure, members acted on by the pressure fluid to control the flow of power medium through said conduit, release means for the fluid, a valve in said last means normally held in closed position by the 1 pressure of discharge refrigerant, a float in the evaporator, and means actuated by the float to render the pressure of the refrigerant ineffective to thereby open said valve and cause said release means to cut off the supply of power medium.

9. In a refrigerating system, an evaporator,

means to supply a power medium to be expended in removing "vapor'from the evaporator, a conduit and pump to discharge refrigerant from the evaporator, a device to place a fluid under pressure, means actuated by the pressure fluid to control the flow of said power medium, a

sure-responsive means including a member acted' on by liquid discharged by the pump to control the operation of the evacuator, and means responsive to a certain level of the liquid in the evaporator to eflect a decrease in the pressure of the liquid acting on said member to cause the member to stop the operation of-the evacuator.

11. In a refrigerating system, anevaporator having inlet means for liquid, a 'pump for removing liquid from the evaporatorfan evacuator for removing vapor from the evaporator, pressure-responsive means including 'a member acted on by liquid discharged by the pump and acting responsively to a falling pressure of such liquid to-stop the operation of the evacuator, and means responsive to a certain level of the liquid in the evaporator to relieve'the pressure of the liquid acting on said member.

12. In a refrigerating system, an evaporator having inlet and discharge means for liquid, a rotary evacuator for removing vapor from the evaporator, a fluid actuated motor for driving the evacuator, a conduit for supplying power fluid to the motor, pressure-actuated governor means comprising a pressure-responsive valve in the conduit and a pump driven by the motor and evacuator for supplying pressure fluid for actuating the valve, a release connection for the ressure fluid, a pressure-responsive valve in he connection normally held closed by the pressure of the liquid discharging from the evaporator, and means for eflectinga reduction in the pressure of the liquid acting on the last said valve to open the valve, relieve the pressure fluid and cause the first said valve to cut oil? the flow of power fluid to the motor. v

4 under pressure to the fluid operated 13. In a refrigerating system comprising an evaporator and a variable speed unit to remove vapor from the evaporator, means to supply a power medium to the unit, valve means to control the supply means, fluid pressure operated means to control the valve means, and means to supply fluid under pressure to the fluid pressure operated means operated by said va riable speed unit and varying the pressure in accordance with variations in the speed of the unit, and separate fluid actuated means to control operation of the last said means.

14. In a refrigerating system comprising an evaporator and a variable speed unit to remove vapor from the evaporator, means to supply power medium to the unit, valve means to control the supply means, manual means to regulate the valve means, fluid pressure operated'means to control the'valve means, means to supply fluid eans 0perated by said variable speed unit a d varying the .pressure in accordance with variations in the speed of the unit, and fluid actuated means to control operation of the last said means.

15. In a refrigerating system comprising an evaporator and a variable speed unit to remove vapor from the evaporator, means to supply a power medium to the unit, fluid pressure operated piston valve means to control the supply means, means to supply fluid under pressure to the valve means operated by said variable speed unit and varying the pressure in accordance with variations in the speed of the unit, and fluid actuated means to normally permit said .fluid under pressure to control the valve means.

16. In a refrigerating system having an evaporator and a variable speed power medium actuated' unit to remove vapor therefrom, fluid pressure operated means to control the supply of power medium to the unit, manual means to operate the fluid pressure operated means to efiect starting of the unit, means controlled by the unit to supply a fluid under a pressure varying in accordance with the speed of the unit, and a fluid pressure operated device associated with the fluid pressure operated means and the manual means to prevent operation of said unit at speeds in excess of a predetermined speed.

17. In a refrigerating system'having an evap- -orator and a variable speed power medium actuated unit to remove vapor therefrom, fluid pressure operated means to control the supply of power medium to the unit thereby controlling the speed of the unit, manual means to operate the fluid pressure operated means to effect starting of the unit, means controlled by the unit to supply a' fluid under pressure to the fluid pressure operated means and varying the JoHN KIRGAN. JOHN A. MACLEAN. GEORGE .H. WOODARD. 

